One of the first ornamental fish in the hobby (pre-dating the Goldfish in Europe). Paradise Fish are stunning, hardy, subtropical Anabantoids. However, they are notoriously aggressive, often exceeding the aggression of Bettas. They are cold-tolerant and thrive in unheated indoor aquariums, but they will readily attack smaller tank mates, eat fry, and fight conspecifics to the death.
At a Glance
Tank Requirements
Water Parameters
Temperament & Compatibility
Available Varieties
Each variety inherits the species defaults above. Only differences are highlighted.
Male (Standard / Color Morphs)
The standard male form. Features long, flowing filaments on the forked tail and dorsal fin. Extremely territorial and aggressive. Must be kept singly. Will kill small fish (Neon Tetras, Guppies) and fight other anabantoids.
Differs in 3 traits from base species
Also known as: Blue, Red, Albino, Black, Super Red
Female
Smaller, duller color, and shorter fins (lacking long filaments). While less aggressive than males, they are still 'nasty' compared to other Gouramis and will nip fins. Can be kept in groups if the tank is large and heavily planted.
Differs in 4 traits from base species
Paradise Fish Care Summary
The Paradise Fish, scientifically known as Macropodus opercularis, belongs to the Anabantoids family group. Adults reach a maximum size of approximately 10 cm and have a compressed body shape with a moderate growth rate. Classified as aggressive, this species primarily occupies the surface and mid-level zones of the aquarium and produces a medium level of biological waste.
To thrive, the Paradise Fish requires a freshwater only aquarium with a minimum volume of 75 litres and a tank length of at least 80 cm. Water temperature should be maintained between 16°C and 26°C, with a pH range of 6–8 and a general hardness of 5–30 dGH. A low water flow is preferred. To replicate their natural habitat, the tank should include plants - densely covered and plants - floating.
Only one Paradise Fish should be kept per aquarium. Keepers should be aware that this species may nip the fins of slow-moving or long-finned tankmates, can be aggressive toward its own kind, will defend a territory within the tank, and is a known jumper, so a tight-fitting lid is essential. This species is available in 2 varieties: Male (Standard / Color Morphs) and Female. Each may differ slightly in size, temperament, or care needs, so it is worth checking the specific requirements of the variety you plan to keep.
Similar Species
Goldfish (Comet / Common)
Carassius auratus
One of the most commonly kept and misunderstood fish in the hobby. Single-tailed goldfish (Comets, Commons, Shubunkins) are fast-growing, highly active coldwater fish that produce enormous amounts of waste. They are best suited for ponds or massive aquariums. They will uproot plants, sift substrate constantly, and eat anything that fits in their mouths.
Betta (Siamese Fighting Fish)
Betta splendens
The Siamese Fighting Fish is an aquarium icon known for its labyrinth organ (allowing air breathing) and vivid colors. While hardy, they require heated, filtered water (24-30°C). Males are solitary and fiercely territorial. Females are generally less ornate but can be kept in 'sororities' with strict precautions (minimum 5 females in 75L+).
Guppy
Poecilia reticulata
One of the most iconic and widely kept aquarium fish. Renowned for their incredible colors, hardiness, and prolific breeding. As livebearers, they give birth to fully formed, free-swimming fry. Males constantly pursue females for mating; therefore, a ratio of at least 2 females per male is strongly recommended to disperse stress.
Cherry Shrimp
Neocaridina davidi
One of the most popular and hardy freshwater invertebrates in the hobby. They come in a rainbow of selectively bred colors. They are excellent scavengers and algae eaters, perfect for nano planted tanks. They are completely peaceful and have a negligible bioload, though they are highly vulnerable to predation by almost any fish with a mouth large enough to eat them.
Freshwater Angelfish
Pterophyllum scalare
The most iconic South American Cichlid, known for its distinct arrowhead shape and majestic fins. While domestic strains are hardy, they remain cichlids: they are semi-aggressive predators that will eat any fish small enough to fit in their mouths (like Neon Tetras). They form loose shoals as juveniles but pair off and become territorial as they mature. Height is more important than length for this species.
Threadfin Rainbowfish
Iriatherina werneri
A delicate and exquisitely shaped nano rainbowfish native to New Guinea and Northern Australia. They are famous for the males' long, filamentous fins and butterfly-like display behavior. Due to their incredibly small throats, they require micro-foods. They are shoaling fish that are easily intimidated by boisterous tank mates.